The goals of this study are to identify population specific determinants of asthma morbidity and mortality and to clarify their interrelationships in order to develop intervention strategies for an inner city population, in children, ages 4-11. This will be accomplished by a national cooperative study consisting of Asthma Study Units. The objectives are to estimate the prevalence of asthma in East Harlem and to characterize the physiological, psychosocial and environmental characteristics that may affect the prevalence and severity of asthma. The proposed study will proceed in two phases. Phase I will identify a study population consisting of 150 asthma cases derived from an inner city community, East Harlem, New York, and 150 cases from the Mount Sinai Medical Center patient population. Non-asthmatic children from the community will be selected as controls. Case-control and longitudinal study design methods will be used to evaluate physiological, psychosocial, and environmental factors that contribute to asthma morbidity in the target population. Environmental hygiene data will be collected on a sub-sample of cases and controls. During Phase II, we will implement and evaluate community-based and medical center-based interventions that are intended to reduce asthma morbidity among the cases identified in Phase I. A random factorial study design will be used to evaluate the relative effectiveness of community-based education, case management based either in schools or a hospital emergency room, and use of clinical treatment protocols. The specific contents and methods of the interventions will be derived based on the information from Phase I.